Device and method for producing high-purity CO2, 13C and 12C through efficient negative-pressure low-temperature rectification

Abstract

The invention relates to a device and method for producing high-purity CO2, 13C and 12C through efficient negative-pressure low-temperature rectification, the device uses CO2 as a raw material, high-boiling-point impurities and low-boiling-point impurities in industrial CO2 gas are removed through a liquid nitrogen cold well and a CO2 low-temperature adsorption film, and the device is composed of an industrial CO2 purification system and 13Camp; high-purity CO2 low-temperature rectification air separation pressure nitrogen supply is carried out, and 13Camp is achieved; the system is composed of an industrial CO2 purification system, a high-purity CO2 efficient negative-pressure low-temperature rectification system, a 13C high-precision filling system, a 12C filling system, a high-purity CO2 filling system, an instrument electric control system and a vacuumizing system, wherein the industrial CO2 purification system is connected with the 13Camp through a pipeline; the high-purity CO2 high-efficiency negative-pressure low-temperature rectification system is connected with the industrial CO2 purification system and the 13Camp; a high-purity CO2 low-temperature rectification air separation pressure nitrogen supply system is adopted, and 13 Camp is achieved; and the high-purity CO2 efficient negative-pressure low-temperature rectification system, the 13C high-precision filling system, the 12C filling system and the high-purity CO2 filling system are respectively connected with the instrument electric control system and the vacuumizing system.

Description

Technical Field

[0001] This invention belongs to the field of stable isotope separation and distillation technology, and relates to a method for producing high-purity CO2 by low-temperature negative pressure distillation. 13 C 12 The apparatus and production method of C. Background Technology

[0002] Stable isotopes are extremely rare in nature and difficult to separate, making it quite challenging to achieve industrial-scale production of isotopes using cryogenic distillation. 13 Carbon (C) and high-purity CO2 have crucial applications in the nuclear industry, cancer prognosis and treatment, nuclear magnetic resonance imaging (MRI), superalloy steel, and ultra-high pressure vessels. Isotope separation and extraction technology has long been monopolized by developed Western countries, and China currently lacks industrial-scale production. Given the importance of isotopes in many key fields, developing industrial-scale production based on low-temperature distillation under negative pressure is essential. 13 C and high-purity CO2 production technologies are of great significance at the national strategic level.

[0003] Therefore, a high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 was designed. 13 C 12 The apparatus and production method of C overcome the above problems. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a highly efficient negative pressure low-temperature distillation method for producing high-purity CO2. 13 C 12 The invention relates to an apparatus and production method for CO2. Industrial CO2 is used as a raw material, and high-boiling-point impurities and low-boiling-point impurities (impurity content not exceeding 5 ppm) are removed from the industrial CO2 through a liquid nitrogen cold well and a low-temperature CO2 adsorption membrane. The invention produces high-purity CO2 and... 13 Product C production employs a cascaded tower configuration. The initial cascade consists of structured packed towers in series, capable of handling large quantities of CO2 feed gas and providing a stable and reliable primary feed gas for subsequent enrichment and concentration. The final cascade consists of random Heli-pak packed towers in series, utilizing the extremely high separation efficiency of random packing to purify CO2 gas while rapidly concentrating it at the top and bottom of the towers. 12 C and 13 C, the resulting product has an atomic abundance of 99.5%. 12 C. Over 85% 13 C and CO2 with a chemical purity of 99.9999% (V / V). This invention utilizes cold nitrogen gas obtained from the vaporization of liquid nitrogen in air separation (or cold nitrogen gas directly from air separation) as the system's cold source. While effectively utilizing the cooling capacity of the air separation system, it significantly reduces the energy consumption level of similar devices, and also eliminates the need for rotating equipment such as expanders, thus saving on equipment investment.

[0005] This invention is achieved through the following technical solution: a high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2. 13 C 12 Device C utilizes CO2 as a raw material and removes high-boiling-point and low-boiling-point impurities from industrial CO2 gas using a liquid nitrogen cooling well and a low-temperature CO2 adsorption membrane. This device comprises an industrial CO2 purification system. 13 C& High-purity CO2 cryogenic distillation air separation pressure nitrogen supply 13 C& High-purity CO2 high-efficiency negative pressure low-temperature distillation system 13 C-precision filling system, 12 The system consists of eight parts: a CO2 filling system, a high-purity CO2 filling system, an instrumentation and electrical control system, a vacuum system, and so on. The industrial CO2 purification system is connected to... 13 Connect to the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system. 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system is connected to... 13 C-precision filling system, 12 The C-filling system is connected to the high-purity CO2 filling system for filling. 13 C-temperature distillation air separation pressure nitrogen supply is 13 The C-type cryogenic distillation system provides cooling; liquid nitrogen from the air separation unit is vaporized and reheated in an air-bath vaporizer to produce cold nitrogen gas, which is then used for... 13 The cold source for the C-temperature distillation system, and the industrial CO2 purification system. 13 C& High-purity CO2 cryogenic distillation air separation pressure nitrogen supply system 13 C& High-purity CO2 high-efficiency negative pressure low-temperature distillation system 13 C-precision filling system, 12 The C-filling system and the high-purity CO2 filling system are also connected to the instrumentation and control system and the vacuum system, respectively.

[0006] Preferably, the industrial CO2 purification system consists of a CO2 tanker truck, a CO2 cold well, and a CO2 low-temperature adsorption membrane. The CO2 tanker truck is connected to the CO2 cold well via a pipeline, and the CO2 low-temperature adsorption membrane is sequentially connected to the CO2 cold well. 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system is connected to input high-purity CO2 feed gas to the downstream. 13 In the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system, an industrial CO2 feed gas shut-off valve is installed on the pipeline between the CO2 tanker and the CO2 cold well. The CO2 cold well is equipped with internal insulation cotton, and a CO2 low-temperature adsorption membrane is used for... 13 The pipeline between the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system and the high-purity CO2 feed gas mass flow controller and high-purity CO2 feed gas pressure gauge are installed.

[0007] As a preferred option: the 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system consists of a CO2 feed purification tower, 13 C-type distillation double-layer wire mesh structured packed column, 13 The high-efficiency Dikesson packed column for C-distillation consists of a CO2 distillation tower, in which the high-purity CO2 feed gas sequentially enters a CO2 feed purification tower, a CO2 feed purification tower, and so on. 13 C-type distillation double-layer wire mesh structured packed column, 13 C-type distillation high-efficiency Dickson loose packing tower, among which 13 The C-type distillation double-layer wire mesh structured packed column is directly connected to the high-purity CO2 filling system. 13 C-distillation high-efficiency Dickson packing tower respectively with 13 C High-precision filling system box 12 The C-filling system is connected, and the high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system is connected to... 13 C-type distillation double-layer wire mesh structured packed column connection, continuously supplying the entire 13 The C& high-purity CO2 high-efficiency negative pressure cryogenic distillation system provides nitrogen.

[0008] Preferably, the high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system includes an air bath vaporizer and an air separation nitrogen pipeline and an air separation liquid nitrogen pipeline located in front of the air bath vaporizer. A liquid nitrogen outlet shut-off valve is installed on both the air separation nitrogen pipeline and the air separation liquid nitrogen pipeline. A distillation system cold source nitrogen regulating valve and a distillation system cold source nitrogen pressure valve are installed behind the air bath vaporizer.

[0009] As a preferred option: the 13 The C high-precision filling system consists of 13 C Liquid Collector 13 C vaporization pressurization electric heater, 13 C-temperature rewarming device, 13 It consists of a gas filling mass flow controller and a milligram-level electronic balance, among which... 13 Product C's airflow outlet is configured with two pipes, one of which flows into... 13 In liquid collector C, another pipe flows into... 13 In the C reheating device, 13 The C rewarming device is equipped with an external... 13 C vaporization pressurized electric heater, in 13 The C rewarming device is located behind the device. 13 Product C filling mass flow controller, through 13 Product C's filling mass flow controller directs the flow into the cylinder, and a milligram-level electronic balance is installed below the cylinder to measure its capacity.

[0010] As a preferred option: the 12 The C-filling system consists of12 C-filled liquid collection tank, 12 C-temperature rewarming device, 12 It consists of a C-gas filling mass flow controller and a gram-level precision electronic balance; among which... 12 Two pipes are installed in front of the C-filled liquid collection tank, one of which connects to... 12 Product C gas, another pipe connects to heated nitrogen gas, and then... 12 The C-type reheating device is connected for reheating, and after reheating, the contents are stored in a steel cylinder. A gram-precision electronic balance is installed below the cylinder. 12 The two pipes at the front of the C-filled liquid collection tank are respectively equipped with 12 C liquid shut-off valve and 12 C. Heated nitrogen shut-off valve, 12 The bottom of the C-filled liquid collection tank is equipped with a nitrogen venting channel, and the top is equipped with... 12 C gas breathing valve, in 12 C-filled liquid collection tank and 12 C reheating device is provided with 12 C-vaporizing pressure unit, 12 A reheating device is installed between the gas cylinder and the C-type reheating device. 12 C-gas filling mass flow controller.

[0011] Preferably, the high-purity CO2 filling system consists of a high-purity CO2 liquid collection tank and a high-purity CO2 gas reconstituted flexible coil. The high-purity CO2 liquid collection tank is equipped with a high-purity CO2 gas inlet pipe and a heated nitrogen inlet pipe. The pipes are respectively equipped with a high-purity CO2 liquid shut-off valve and a high-purity CO2 heated nitrogen shut-off valve. A nitrogen venting channel is provided below the high-purity CO2 liquid collection tank, and a high-purity CO2 gas breather valve is provided above it. The high-purity CO2 gas reconstituted flexible coil is connected to a gas cylinder at the rear.

[0012] Preferably, the vacuum system consists of a rotary vane vacuum pump and a silencer. The vacuum pump is connected to the entire system via a pipeline. A vacuum diaphragm valve and a vacuum resistance gauge are installed on the pipeline, and a one-way valve is installed behind the silencer.

[0013] A high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 13 C 12 A method for producing the apparatus of C, the method comprising the following steps: 1) System preprocessing: This includes checking the system piping, visual inspection, and checking for errors during startup; if no problems are found, proceed to the next step; if problems are found, issue an alarm for further inspection. 2) Vacuuming: Nitrogen purging is used for 5-8 hours. 3) When the nitrogen in the system reaches the set value, industrial CO2 is introduced and purified to remove impurities, generating high-purity CO2 raw material gas; 4) It enters the low-temperature purification distillation column, where high-purity CO2 feed gas is generated at the top of the distillation column; 5) High-purity CO2 feed gas enters 13 The reaction is carried out in a C-type negative pressure low-temperature distillation column to produce high-purity CO2. 13 C 12 C; 6) Separately, high-purity CO2, 13 C 12 C is filled using its own filling system.

[0014] As a preferred embodiment, the specific method for purification and impurity removal in step 3) is as follows: 1) Industrial CO2 gas high-boiling-point impurities removal cold well removes high-boiling-point impurities from industrial CO2, mainly including water, carbon dioxide and hydrogen sulfide, reducing their content to below 500 ppm. 2) CO2 gas: The CO2 low-temperature adsorption membrane mainly removes low-boiling-point impurities from CO2, and the overall content of CO2 gas impurities is reduced to less than 6 ppm through the CO2 low-temperature adsorption membrane. 3) The high-purity CO2 feed gas mass flow controller is mainly used to count the amount of CO2 feed gas used, in order to further improve... 13 C extraction rate is used as a reference.

[0015] As a preferred embodiment, the specific method in the low-temperature purification distillation column in step 4) is as follows: First, the material enters the purification distillation column for purification. Then, this invention employs a cascade arrangement of high-efficiency structured packed columns and random Heli-pak packed columns connected in series, with a total of m stages of structured packed columns and n stages of random Heli-pak packed columns. The first-stage distillation column uses a conventional purification distillation column, while the second-stage distillation process uses a structured packed column. The structured distillation column can provide a basis for subsequent enrichment. 13 C provides a large quantity of semi-finished products. Random packing has a smaller feed gas handling capacity compared to structured packing, but the equivalent theoretical plate number of random packing is much higher than that of structured packing. 13 The latter half of the cascaded C enrichment system is designed with n+1 stages of random Heli-pak packed towers, while the m-stage structured packed towers are mainly used for large-scale separation. 12 C gas, thus obtaining crude 13 C is the feed gas; the latter half, n+1 stages of the random-packed Heli-pak tower, utilizes the ultra-high separation efficiency of random-packed materials to rapidly enrich the gas in the top phase. 13 C gas.

[0016] As a preferred option: the 13Gas C is obtained at the bottom of the final stage of the scattered Heli-pak packed tower, and this gas enters... 13 Product C accumulates in the liquefaction collector, and is then vaporized and pressurized by the bottom electric heater. 13 Product C gas passes through 13 Product C gas is reheated to room temperature via flexible winding in a tube. 13 Product C's filling quality flow controller controls the filling flow rate, and finally... 13 The C-grade electronic balance accurately measures the filling amount of the steel cylinder using milligram-level precision.

[0017] As a preferred option: the 12 C gas is collected at the top of the final stage random-pile Heli-pak packed tower. 12 Product C is first stored in 12 C. Liquid collection tank, when it needs to be filled, 12 Nitrogen gas at room temperature is introduced into liquid collection tank C as a... 12 C vaporization pressurization heat source, through 12 Product C gas recovery flexible winding tube 12 C. Reheat to room temperature. 12 The C product filling quality flow controller is used to control... 12 C. Gas filling speed, cylinder filling mass is determined by 12 Product C is filled using a gram-level electronic balance.

[0018] As a preferred option: the 13 The exhaust gas from the C-type negative pressure low-temperature distillation system is high-purity CO2 gas. It can be collected periodically into a high-purity CO2 liquid collection tank. When vaporization and filling are required, room temperature nitrogen can be used for vaporization and pressurization. Then, high-purity CO2 gas is used for warming and reheating in a flexible winding tube to room temperature. Finally, the cylinder is filled directly using the partial pressure method.

[0019] The beneficial effects of this invention are as follows: This invention designs a high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2. 13 C 12 The apparatus and production method for C use purified industrial CO2 gas as raw material and enrich it in the form of a multi-stage negative pressure low temperature cascade tower. 13 C and 12 C, Concentrate step-by-step at the bottom of a low-pressure, low-temperature distillation column. 13 C, obtained from the top of the tower 12 C. Suitable for industrial-scale production, the first few stages of the negative pressure cryogenic distillation column of this invention use high-efficiency structured packing, enabling large-scale processing of feed gas. The last few stages of the negative pressure cryogenic distillation column use high-efficiency Heli-pak random packing, greatly improving... 13C Extraction rate. This invention fully utilizes the vaporization of liquid nitrogen in air separation to provide a cold source for the entire distillation system, significantly reducing the energy consumption of the entire unit while effectively utilizing the cold source of the air separation equipment. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 for Figure 1 Schematic diagram of a CO2 gas purification device for industrial use; Figure 3 for Figure 1 middle 13 Schematic diagram of a multi-stage series C isotope negative pressure cryogenic distillation column; Figure 4 for 13 Schematic diagram of the pressure nitrogen supply structure for C-temperature distillation air separation; Figure 5 for 13 Schematic diagram of the C isotope liquefaction followed by vaporization and pressurization filling structure; Figure 6 for 12 Schematic diagram of the C isotope liquefaction followed by vaporization and pressurization filling structure; Figure 7 Schematic diagram of a high-purity CO2 gasification pressurized filling structure; Figure 8 This is a schematic diagram of the system's vacuuming structure; Figure 9 This is the electrical structure of the present invention; Figure 10 This is a flowchart of the workflow of the present invention. Detailed Implementation

[0021] To enable those skilled in the art to more clearly understand the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0022] In the description of this invention, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "lateral", and "vertical" is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing this invention, and is not intended to indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be construed as a limitation of this invention.

[0023] The invention will now be described in detail with reference to the accompanying drawings: Figure 1 As shown, a high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2... 13 C 12Device C utilizes CO2 as a raw material and removes high-boiling-point and low-boiling-point impurities from industrial CO2 gas using a liquid nitrogen cooling well and a low-temperature CO2 adsorption membrane 5. This device comprises an industrial CO2 purification system. 13 C& High-purity CO2 cryogenic distillation air separation pressure nitrogen supply 13 C& High-purity CO2 high-efficiency negative pressure low-temperature distillation system 13 C-precision filling system, 12 The system consists of eight parts: a CO2 filling system, a high-purity CO2 filling system, an instrumentation and electrical control system, a vacuum system, and so on. The industrial CO2 purification system is connected to... 13 Connect to the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system. 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system is connected to... 13 C-precision filling system, 12 The C-filling system is connected to the high-purity CO2 filling system for filling. 13 C-temperature distillation air separation pressure nitrogen supply is 13 The C-type cryogenic distillation system provides cooling; liquid nitrogen from the air separation unit is vaporized and reheated in an air-bath vaporizer to produce cold nitrogen gas, which is then used for... 13 The cold source for the C-temperature distillation system, and the industrial CO2 purification system. 13 C& High-purity CO2 cryogenic distillation air separation pressure nitrogen supply system 13 C& High-purity CO2 high-efficiency negative pressure low-temperature distillation system 13 C-precision filling system, 12 The C-filling system and the high-purity CO2 filling system are also connected to the instrumentation and control system and the vacuum system, respectively.

[0024] The industrial CO2 purification system consists of a CO2 tanker truck 46, a CO2 cooling well 4, and a CO2 low-temperature adsorption membrane 5. The CO2 tanker truck 46 is connected to the CO2 cooling well 4 via a pipeline, and the CO2 low-temperature adsorption membrane 5 is connected sequentially to the CO2 cooling well 4. 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system is connected to input high-purity CO2 feed gas to the downstream. 13 In the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system, an industrial CO2 feed gas shut-off valve 42 is installed on the pipeline between the CO2 tanker 46 and the CO2 cold well 4. The CO2 cold well 4 is equipped with internal insulation cotton 41. A CO2 low-temperature adsorption membrane 5 and... 13 The pipeline between the C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system is equipped with a high-purity CO2 feed gas mass flow controller 6 and a high-purity CO2 feed gas pressure device 38.

[0025] The 13 The C& high-purity CO2 high-efficiency negative pressure low-temperature distillation system consists of a CO2 feed purification tower,13 C-type distillation double-layer wire mesh structured packed tower 1 13 The C-type high-efficiency Dikes loose packed tower 41 is composed of CO2 distillation high-purity feed gas, which sequentially enters the CO2 feed purification tower, CO2 feed purification tower, and so on. 13 C-type distillation double-layer wire mesh structured packed tower 1 13 C-distillation high-efficiency Dickson packing tower 41, of which 13 C-type distillation double-layer wire mesh structured packed column 1 is directly connected to the high-purity CO2 filling system. 13 C-distillation high-efficiency Dixon packed tower 41 and respectively with 13 C High-precision filling system box 12 The C-filling system is connected, and the high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system is connected to... 13 C-type distillation double-layer wire mesh structured packed column 1 is connected, continuously supplying the entire... 13 The C& high-purity CO2 high-efficiency negative pressure cryogenic distillation system provides nitrogen.

[0026] The high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system includes an air bath vaporizer 8 and an air separation nitrogen pipeline and an air separation liquid nitrogen pipeline located in front of the air bath vaporizer 8. A liquid nitrogen outlet cold box shut-off valve 7 is installed on both the air separation nitrogen pipeline and the air separation liquid nitrogen pipeline. A distillation system cold source nitrogen regulating valve 9 and a distillation system cold source nitrogen pressure valve 10 are installed behind the air bath vaporizer 8.

[0027] The 13 The C high-precision filling system consists of 13 C Liquid Collector 15 13 C vaporization pressurization electric heater, 13 C. Reheating device 16 13 It consists of a gas filling mass flow controller 17 and a milligram-level electronic balance 19, wherein... 13 Product C's airflow outlet is configured with two pipes, one of which flows into... 13 In liquid collector 15, another pipe flows into... 13 In the C reheating device 16, the 13 C. The rewarming device 16 is externally equipped with 13 C vaporization pressurized electric heater, in 13 The C rewarming device is located behind the device. 13 Product C is filled with mass flow controller 20, through 13 Product C's filling mass flow controller 20 flows into the steel cylinder, and a milligram-level electronic balance 18 is installed below the steel cylinder for measuring the capacity.

[0028] The 12 The C-filling system consists of 12 C-filled liquid collection tank 22, 12C. Reheating device 21 12 It consists of a C-gas filling mass flow controller 20 and a gram-level precision electronic balance 19; among which... 12 Two pipes are installed in front of the C-filled liquid collection tank, one of which connects to... 12 Product C gas, another pipe connects to heated nitrogen gas, and then... 12 The reheating device 21 is connected for reheating, and after reheating, the contents are stored in a steel cylinder. A gram-precision electronic balance 19 is installed below the steel cylinder. 12 The two pipes at the front of the C-filled liquid collection tank 22 are respectively provided with 12 C liquid shut-off valve 25 and 12 C. Heated nitrogen shut-off valve 24, 12 A nitrogen venting channel is provided below the C-filled liquid collection tank 22, and a [missing information - likely a venting channel] is provided above it. 12 C gas breathing valve 32, in 12 C-filled liquid collection tank 22 and 12 A rewarming device 21 is provided with 12 C vaporizer pressure unit 23 12 A reheating device 21 is installed between the gas cylinder and the C reheating device 21. 12 C Gas Filling Mass Flow Controller 20.

[0029] The high-purity CO2 filling system consists of a high-purity CO2 liquid collection tank 28 and a high-purity CO2 gas reconstituted flexible coil 30. The high-purity CO2 liquid collection tank 28 is equipped with a high-purity CO2 gas inlet pipe and a heated nitrogen inlet pipe, respectively, with a high-purity CO2 liquid shut-off valve 26 and a high-purity CO2 heated nitrogen shut-off valve 27 on each pipe. A nitrogen venting channel is located below the high-purity CO2 liquid collection tank 28, and a high-purity CO2 gas breather valve 31 is located above it. The high-purity CO2 gas reconstituted flexible coil 30 is connected to a gas cylinder at the rear. A high-purity CO2 pressure device 29 is also installed on the high-purity CO2 liquid collection tank 28.

[0030] The vacuum system consists of a rotary vane vacuum pump 33 and a silencer 37. The vacuum pump is connected to the entire system via a pipeline. A vacuum diaphragm valve 34 and a vacuum resistance gauge 35 are installed on the pipeline. A one-way valve 36 is installed behind the silencer 37.

[0031] A high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 13 C 12 A method for producing the apparatus of C, the method comprising the following steps: 1) System preprocessing: This includes checking the system piping, visual inspection, and checking for errors during startup; if no problems are found, proceed to the next step; if problems are found, issue an alarm for further inspection. 2) Vacuuming: Nitrogen purging is used for 5-8 hours. 3) When the nitrogen in the system reaches the set value, industrial CO2 is introduced and purified to remove impurities, generating high-purity CO2 raw material gas; 4) It enters the low-temperature purification distillation column, where high-purity CO2 feed gas is generated at the top of the distillation column; 5) High-purity CO2 feed gas enters 13 The reaction is carried out in C-pressure low-temperature distillation column 1 to generate high-purity CO2. 13 C 12 C; 6) Separately, high-purity CO2, 13 C 12 C is filled using its own filling system.

[0032] The specific method for purification and impurity removal in step 3) is as follows: 1) Industrial CO2 gas high-boiling-point impurities removal cold well 4 removes high-boiling-point impurities from industrial CO2, mainly including water, carbon dioxide and hydrogen sulfide, reducing their content to below 500 ppm. 2) CO2 gas: The CO2 low-temperature adsorption membrane mainly removes low-boiling-point impurities from CO2, and the overall content of CO2 gas impurities is reduced to less than 6 ppm through the CO2 low-temperature adsorption membrane. 3) The high-purity CO2 feed gas mass flow controller 6 is mainly used to count the amount of CO2 feed gas used, in order to further improve... 13 C extraction rate is used as a reference.

[0033] The specific method in the low-temperature purification distillation column in step 4) is as follows: First, the sample enters the purification distillation column for purification. Then, this invention employs a cascade arrangement of high-efficiency structured packed columns and random Heli-pak packed columns connected in series, with a total of m stages of structured packed columns and n stages of random Heli-pak packed columns. The first-stage distillation column uses a conventional purification distillation column, while the second-stage distillation process uses a structured packed column. The structured distillation column can provide a basis for subsequent enrichment. 13 C provides a large quantity of semi-finished products. Random packing has a smaller feed gas handling capacity compared to structured packing, but the equivalent theoretical plate number of random packing is much higher than that of structured packing. 13 The latter half of the cascaded C enrichment system is designed with n+1 stages of random Heli-pak packed towers, while the m-stage structured packed towers are mainly used for large-scale separation. 12 C gas, thus obtaining crude 13 C is the feed gas; the latter half, n+1 stages of the random-packed Heli-pak tower, utilizes the ultra-high separation efficiency of random-packed materials to rapidly enrich the gas in the top phase. 13 C gas.

[0034] Among them, the 13Gas C is obtained at the bottom of the final stage of the scattered Heli-pak packed tower, and this gas enters... 13 Product C accumulates in the liquefaction collector, and is then vaporized and pressurized by the bottom electric heater. 13 Product C gas passes through 13 Product C gas is reheated to room temperature via flexible winding in a tube. 13 Product C's filling quality flow controller controls the filling flow rate, and finally... 13 The C-grade electronic balance accurately measures the filling amount of the steel cylinder using milligram-level precision. 12 C gas is collected at the top of the final stage random-pile Heli-pak packed tower. 12 Product C is first stored in 12 C. Liquid collection tank, when it needs to be filled, 12 Nitrogen gas at room temperature is introduced into liquid collection tank C as a... 12 C vaporization pressurization heat source, through 12 Product C gas recovery flexible winding tube 12 C. Reheat to room temperature. 12 The C product filling quality flow controller is used to control... 12 C. Gas filling speed, cylinder filling mass is determined by 12 Product C is filled using a gram-level electronic balance.

[0035] The 13 The exhaust gas from the C-type negative pressure low-temperature distillation system is high-purity CO2 gas. It can be collected periodically into a high-purity CO2 liquid collection tank. When vaporization and filling are required, room temperature nitrogen can be used for vaporization and pressurization. Then, high-purity CO2 gas is used for warming and reheating in a flexible winding tube to room temperature. Finally, the cylinder is filled directly using the partial pressure method.

[0036] The industrial CO2 purification system first removes high-boiling-point impurities (mainly including moisture, carbon dioxide, and hydrogen sulfide) from industrial CO2 through a cold well, reducing their content to below 500 ppm. The system's low-temperature CO2 purification membrane adsorbs and removes low-boiling-point substances such as carbon monoxide, hydrogen, and nitrogen at low temperatures, reducing their content to below 6 ppm. The cold well in the industrial CO2 purification system is achieved through an open liquid nitrogen Dewar flask, using an atmospheric pressure liquid nitrogen bath to control the content of high-boiling-point impurities in the industrial CO2 gas at a low level, generally below 500 ppm. The open liquid nitrogen Dewar flask has a slag discharge port inside to remove high-boiling-point solidified impurities.

[0037] The purification of low-boiling-point impurity gases in industrial CO2 is achieved through a low-temperature adsorption membrane. Industrial CO2 gas exiting the cold well passes through the membrane, where low-boiling-point impurities are adsorbed, reducing the impurity content to below 6 ppm. The low-temperature CO2 purification tower further reduces the impurity content to below 1 ppm. This tower is heated by an electric heater, and the top cold source is cold nitrogen from an air separation unit. 13 C-temperature distillation air separation pressure nitrogen supply is 13 The C-type cryogenic distillation system provides cooling; liquid nitrogen from the air separation unit is vaporized and reheated in an air-bath vaporizer to produce cold nitrogen gas, which is then used for... 13 C. Low-temperature distillation system cold source. 13 The C-efficiency negative pressure low-temperature distillation system removes CO2... 13 C and 12 C is efficiently separated and enriched at the bottom of the distillation column. 13 C, the top of the distillation column collects... 12 C gas. 13 The high-efficiency negative pressure cryogenic distillation column adopts negative pressure operation, which can effectively improve... 13 C and 12 C is the separation coefficient, and has a smaller theoretical plate number.

[0038] 13 The high-efficiency negative pressure cryogenic distillation column adopts a cascaded configuration, with a total of n distillation columns arranged in series, concentrating the distillation process stage by stage. 13 C and 12 C. 13 The C isotope high-efficiency negative pressure cryogenic distillation column is designed for industrial-scale production. The first few stages use high-efficiency structured packing, while the later stages use scattered Heli-pak rectangular spiral rings. 13 C is scarce, and its filling is controlled by a mass flow controller.

[0039] 13 Product C is first liquefied, and then pressurized by vaporization with nitrogen at room temperature. 13 The C gas is reheated in air through a flexible winding tube, and then the filling amount is precisely controlled by a mass flow controller. 12 C is enriched at the top of the final distillation column, and the cylinder filling rate is controlled by a mass flow controller. 12 In the high-efficiency negative pressure low-temperature distillation process, high-purity CO2 gas is obtained at the bottom of the conditioning column and filled into cylinders via nitrogen vaporization and pressurization at room temperature. The actual filling volume of the cylinders is controlled using a partial pressure method during the filling process. The vacuum pump is a mechanical rotary vane pump with an ultimate vacuum of 0.2 Pa. A vacuum resistance gauge with a limit sensitivity of 0.02 Pa is used to measure the vacuum level at the pump port. The output signal of the vacuum resistance gauge is used to control the operation of the vacuum solenoid shut-off valve. Example

[0040] Figure 2The CO2 low-temperature adsorption membrane 5 mainly removes low-boiling-point impurities from CO2, and the overall content of CO2 gas impurities is reduced to less than 6 ppm through the low-temperature adsorption membrane.

[0041] further, Figure 2 The medium-to-high purity CO2 feed gas mass flow controller 6 is mainly used to count the amount of CO2 feed gas used, in order to further improve... 13 C extraction rate is used as a reference.

[0042] like Figure 3 As shown, 13 C and 12 The average separation coefficient between C plates is usually around 1.003, so separating them requires a huge number of theoretical plates. Figure 3 middle 13 The C-stage low-temperature distillation column adopts a multi-stage series configuration to meet the theoretical plate number requirements of the distillation process.

[0043] Furthermore, this invention employs a cascaded tower arrangement of highly efficient structured packed towers and random Heli-pak packed towers connected in series, comprising a total of m stages of structured packed towers and n stages of random Heli-pak packed towers. This invention is applicable to industrial-scale production. 13 In production process C, to increase the feed gas throughput of the distillation column, a structured packed column was used in the primary distillation process. This structured column offers advantages such as low column resistance drop and high feed gas flow rate. The structured distillation column can then be used for subsequent enrichment... 13 C provides a large quantity of semi-finished products. Random packing has a smaller feed gas handling capacity compared to structured packing, but the equivalent theoretical plate number of random packing is much higher than that of structured packing. This invention... 13 The second half of the cascaded C enrichment system was designed with an n+1-stage random Heli-pak packed tower.

[0044] Furthermore, the aforementioned m-level structured packed towers are mainly used for large-scale separation. 12 C, thus obtaining coarse 13 C raw material; the latter half, n+1 stage random Heli-pak packed tower, utilizes the ultra-high separation efficiency of random packing to rapidly enrich the material in the top gas phase. 13 C.

[0045] like Figure 4 As shown, 13 C. Low-temperature distillation air separation pressure nitrogen supply includes liquid nitrogen outlet cold box shut-off valve 7, air bath vaporizer 8, 9, distillation system cold source nitrogen regulating valve, distillation system cold source nitrogen pressure valve 10, air separation nitrogen shut-off valve 39.

[0046] Furthermore, this invention utilizes liquid nitrogen or nitrogen gas, a byproduct of air separation, as... 13The low-temperature distillation system's cold source fully utilizes the air separation cooling capacity while significantly reducing the operating energy consumption of this invention, eliminating the need for rotating equipment such as expanders, and greatly reducing investment costs.

[0047] Furthermore, the air separation liquid nitrogen is vaporized into cold source nitrogen through the air bath vaporizer 8, and the cold source nitrogen regulating valve 9 of the distillation system is used to regulate the system input cooling capacity.

[0048] like Figure 5 As shown, 13 The C liquefaction followed by vaporization and pressurization filling section includes... 13 C Liquid Collector 15, 13 C. Reheating device 16, 13 17. Gas filling mass flow controller for C gas, 18. Milligram electronic balance.

[0049] Furthermore, the target obtained at the bottom of the final stage random Heli-pak packed tower 13 C gas in 13 Liquid accumulates in collector 15, and then... 13 C. Liquid collector 15: Bottom electric heater vaporizes and pressurizes the liquid.

[0050] Furthermore, after pressurization 13 Product C gas passes through 16, 13 Product C gas is reheated to room temperature via flexible winding in a tube. 13 The gas filling mass flow controller 17 controls the filling flow rate, and finally the filling amount of the cylinder is accurately measured by the milligram-level electronic balance 18.

[0051] like Figure 6 As shown, 12 The C-liquefied vaporization pressurized filling structure includes a milligram-level electronic balance 19. 12 Product C: Filling mass flow controller 20, 12 C. Reheating device 21, 12 C-filled liquid collection tank 22, 12 C vaporizer 23 12 C. Heated nitrogen shut-off valve 24, 12 C liquid shut-off valve 25, 12 C. Gas breathing valve 32.

[0052] further, 12 C is mainly collected at the top of the final stage of the Heli-pak packed tower. 12 Product C is first stored in 12 C. Liquid collection tank. When filling is required, room temperature nitrogen gas is introduced into the exhaust regulating valve 11 at the top of the first-stage structured distillation column as a filling agent. 12 C vaporization pressurization heat source, through 12 C Reheating device 21 will 12C. Reheat to room temperature. 12 Product C filling mass flow controller 20 is used to control 12 The gas filling speed and cylinder filling mass were determined by a milligram-level electronic balance 19.

[0053] like Figure 7 As shown, the high-purity CO2 vaporization pressurization filling structure includes a high-purity CO2 liquid shut-off valve 26, a high-purity CO2 heating nitrogen shut-off valve 27, a high-purity CO2 liquid collection tank 28, a high-purity CO2 gas reconstituted flexible winding tube 30, and a high-purity CO2 gas breathing valve 31.

[0054] 13 The exhaust gas discharged from the C negative pressure low temperature distillation system is high-purity CO2 gas, which can be collected periodically into the high-purity CO2 liquid collection tank 28. When vaporization and filling are required, room temperature nitrogen can be used for vaporization and pressurization, and then the high-purity CO2 gas can be warmed to room temperature through the warming and flexible winding tube 30, and then the cylinder can be directly filled using the partial pressure method.

[0055] like Figure 8 As shown, the vacuum system includes a rotary vane vacuum pump 33, a vacuum diaphragm valve 34, a vacuum resistance gauge 35, a one-way valve 36, a silencer 37, and a system vacuum panel.

[0056] Furthermore, the system's multiple vacuum ports are uniformly arranged on the system's vacuum panel 45, making the piping simple and clear.

[0057] like Figure 9 As shown, the PLC controls the delivery volume of purified CO2 raw material gas, and the actual usage of CO2 raw material gas is accumulated through the high-purity CO2 raw material gas mass flow controller.

[0058] like Figure 9 As shown, the PLC controls the power of the electric heater in the distillation column, thereby controlling the actual evaporation rate in the column.

[0059] like Figure 9 As shown, the PLC controls the flow rate of nitrogen from the cold source, adjusts the system's cooling capacity input, and controls the amount of CO2 vapor condensed in the condenser.

[0060] like Figure 9 As shown, PLC control 13 C. Gas filling mass flow controller 17, thereby regulating 13 Product C: Gas flow rate, cumulative actual filling volume.

[0061] like Figure 9 As shown, PLC control 12 Product C is filled with a mass flow controller 20, thereby regulating the flow rate. 12 Product C: Gas flow rate, cumulative actual filling volume.

[0062] like Figure 9 As shown, the PLC controls the exhaust regulating valve 11 at the top of the first-stage conditioning tower to adjust the tower top. 13 C. Air output.

[0063] like Figure 9 As shown, the PLC controls the exhaust regulating valve 13 at the top of the m-th stage conditioning tower to regulate the top of the tower. 13 C. Air output.

[0064] like Figure 9 As shown, the vacuum resistance gauge 35 triggers a signal that is fed back to the PLC, which then controls the opening and closing of the vacuum shut-off valve 34.

[0065] This invention relates to a high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 and 13 Before starting the C-type technology and equipment, it is necessary to check whether the system pipeline connections are intact and whether the PLC feedback from the instrumentation and control equipment is normal. Before the system is put into operation, the air in the pipeline must be replaced with dry nitrogen, and the vacuum degree of the system pipeline should not exceed 1 Pa.

[0066] Industrial CO2 gas is treated in a cold well (cold source is liquid nitrogen) to remove high-boiling-point impurities, so that the impurity content of CO2 gas does not exceed 500 ppm.

[0067] like Figure 10 As shown, CO2 gas from the cold well removes low-boiling-point impurities in a low-temperature adsorption membrane, and the impurity content of CO2 gas passing through the low-temperature adsorption membrane is controlled to be below 6 ppm.

[0068] Furthermore, the amount of CO2 gas entering the purification tower is controlled by the CO2 raw material gas mass flow controller, while the actual CO2 consumption of the system is accumulated.

[0069] like Figure 10 As shown, 13 C-type filling uses a process of first liquefying, then vaporizing and pressurizing. After vaporization and pressurization... 13 C gas passes through 13 C Reheating device 16 ( 13 Product C gas (reheated to room temperature via flexible winding tube) 13 The C-gas filling mass flow controller 17 and the milligram-level electronic balance 18 enable precise measurement of cylinder filling.

[0070] like Figure 10 As shown, 12 C-filling uses a room-temperature nitrogen vaporization and pressurization filling method. After vaporization and pressurization... 12 C gas passes through 12 Product C gas is reheated to room temperature via flexible winding tube 21, and then... 12 Product C uses a filling mass flow controller 20 and a milligram-level electronic balance 19 to achieve accurate measurement of cylinder filling.

[0071] like Figure 10 As shown, as 13 The byproduct of C-pressure low-temperature distillation, high-purity CO2 liquid, is mainly collected at the bottom of the structured column, and its filling mainly adopts the method of nitrogen vaporization and pressurization at room temperature.

[0072] This invention provides a method for producing high-purity CO2 through efficient negative-pressure low-temperature distillation. 13 The technology and apparatus of C utilize CO2 as a raw material, removing high-boiling-point and low-boiling-point impurities (impurity content not exceeding 5 ppm) from industrial CO2 gas through a liquid nitrogen cold well and a low-temperature adsorption membrane. This invention... 13 Product C is produced using a cascaded tower configuration, with the initial cascade consisting of structured packed towers connected in series. This allows for the processing of large quantities of CO2 feedstock gas, providing a stable and reliable primary for subsequent enrichment and concentration. 13 C is the feed gas; the downstream cascade consists of a series of random Heli-pak packed towers, utilizing the ultra-high separation efficiency of the random packing to rapidly concentrate the gas at the top and bottom of the towers. 12 C and 13 C. This invention uses cold nitrogen obtained from the vaporization of liquid nitrogen in air separation (or directly from air separation) as the system's cold source. While effectively utilizing the cooling capacity of the air separation system, this significantly reduces the energy consumption of the device and eliminates the need for rotating equipment such as expanders, thus saving on equipment investment. Main products of this invention 13 C gas is filled into cylinders by first liquefying it and then vaporizing and pressurizing it with an electric heater. A mass flow controller and a milligram-level electronic balance are used to ensure the accuracy of the cylinder filling quality. 12 C's filling and 13 Similarly, C utilizes nitrogen gas at room temperature for... 13 C is vaporized and pressurized, and then the accuracy of the cylinder filling quality is ensured by using a mass flow controller and a gram-level electronic balance. As a byproduct of the device of this invention, high-purity CO2 is vaporized and pressurized using room-temperature nitrogen, and then directly filled into cylinders using the partial pressure method.

[0073] The specific embodiments described herein are merely illustrative of the principles and effects of the invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this invention should still be covered by the claims of this invention.

Claims

1. A high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2. 13 C 12 The apparatus of type C, which uses CO2 as a raw material, removes high-boiling-point and low-boiling-point impurities from industrial CO2 gas through a liquid nitrogen cooling well and a low-temperature CO2 adsorption membrane, is characterized by: The device consists of an industrial CO2 purification system. 13 C & High-purity CO2 cryogenic distillation air separation pressure nitrogen supply, 13 C & High-purity CO2 high-efficiency negative pressure low-temperature distillation system, 13 C-precision filling system, 12 The system consists of eight parts: a CO2 filling system, a high-purity CO2 filling system, an instrumentation and electrical control system, a vacuum system, and so on. The industrial CO2 purification system is connected to... 13 Connect to a high-purity CO2 high-efficiency negative pressure low-temperature distillation system. 13 C & High-purity CO2 high-efficiency negative pressure low-temperature distillation system are respectively connected to 13 C-precision filling system, 12 The C-filling system is connected to the high-purity CO2 filling system for filling. 13 C-temperature distillation air separation pressure nitrogen supply is 13 The C-type cryogenic distillation system provides cooling; liquid nitrogen from the air separation unit is vaporized and reheated in an air-bath vaporizer to produce cold nitrogen gas, which is then used for... 13 The cold source for the C-temperature distillation system, and the industrial CO2 purification system. 13 C & High-purity CO2 cryogenic distillation air separation pressure nitrogen supply system, 13 C & High-purity CO2 high-efficiency negative pressure low-temperature distillation system, 13 C-precision filling system, 12 The C-filling system and the high-purity CO2 filling system are also connected to the instrumentation and control system and the vacuum system, respectively.

2. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 1. 13 C 12 The device of C is characterized by: The industrial CO2 purification system consists of a CO2 tanker truck, a CO2 cold well, and a CO2 low-temperature adsorption membrane. The CO2 tanker truck is connected to the CO2 cold well via a pipeline, and the CO2 low-temperature adsorption membrane is connected to the CO2 cold well in sequence. 13 The system is connected to a high-purity CO2 high-efficiency negative pressure cryogenic distillation system, which inputs high-purity CO2 feed gas to the downstream... 13 In the C & high-purity CO2 high-efficiency negative pressure low-temperature distillation system, an industrial CO2 feed gas shut-off valve is installed on the pipeline between the CO2 tanker and the CO2 cold well. The CO2 cold well is equipped with internal insulation cotton, and a CO2 low-temperature adsorption membrane is used for... 13 The pipeline between the C and high-purity CO2 high-efficiency negative pressure low-temperature distillation system is equipped with a high-purity CO2 feed gas mass flow controller and a high-purity CO2 feed gas pressure gauge.

3. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 2. 13 C 12 The device of C is characterized by: The 13 C & High-purity CO2 high-efficiency negative pressure low-temperature distillation system consists of CO2 feed purification tower, 13 C-type distillation double-layer wire mesh structured packed column, 13 The high-efficiency Dikesson packed column for C-distillation consists of a CO2 distillation tower, in which the high-purity CO2 feed gas sequentially enters a CO2 feed purification tower, a CO2 feed purification tower, and so on. 13 C-type distillation double-layer wire mesh structured packed column, 13 C-type distillation high-efficiency Dickson loose packing tower, among which 13 The C-type distillation double-layer wire mesh structured packed column is directly connected to the high-purity CO2 filling system. 13 C-distillation high-efficiency Dickson packing tower respectively with 13 C High-precision filling system box 12 The C-filling system is connected, and the high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system is connected to... 13 C-type distillation double-layer wire mesh structured packed column connection, continuously supplying the entire 13 The C & high-purity CO2 high-efficiency negative pressure cryogenic distillation system provides nitrogen.

4. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 3. 13 C 12 The device of C is characterized by: The high-purity CO2 cryogenic distillation air separation pressure nitrogen supply system includes an air bath vaporizer and air separation nitrogen pipeline and air separation liquid nitrogen pipeline located in front of the air bath vaporizer. Liquid nitrogen outlet shut-off valves are installed on both the air separation nitrogen pipeline and the air separation liquid nitrogen pipeline. A distillation system cold source nitrogen regulating valve and a distillation system cold source nitrogen pressure valve are installed behind the air bath vaporizer.

5. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 3. 13 C 12 The device of C is characterized by: The 13 The C high-precision filling system consists of 13 C Liquid Collector 13 C vaporization pressurization electric heater, 13 C-temperature rewarming device, 13 It consists of a gas filling mass flow controller and a milligram-level electronic balance, among which... 13 Product C's airflow outlet is configured with two pipes, one of which flows into... 13 In liquid collector C, another pipe flows into... 13 In the C reheating device, 13 The C rewarming device is equipped with an external... 13 C vaporization pressurized electric heater, in 13 The C rewarming device is located behind the device. 13 Product C filling mass flow controller, through 13 Product C's filling mass flow controller directs the flow into the cylinder, and a milligram-level electronic balance is installed below the cylinder to measure its capacity.

6. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 3. 13 C 12 The device of C is characterized by: The 12 The C-filling system consists of 12 C-filled liquid collection tank, 12 C-temperature rewarming device, 12 It consists of a C-gas filling mass flow controller and a gram-level precision electronic balance; among which... 12 Two pipes are installed in front of the C-filled liquid collection tank, one of which connects to... 12 Product C gas, another pipe connects to heated nitrogen gas, and then... 12 The C-type reheating device is connected for reheating, and after reheating, the contents are stored in a steel cylinder. A gram-precision electronic balance is installed below the cylinder. 12 The two pipes at the front of the C-filled liquid collection tank are respectively equipped with 12 C liquid shut-off valve and 12 C. Heated nitrogen shut-off valve, 12 The bottom of the C-filled liquid collection tank is equipped with a nitrogen venting channel, and the top is equipped with... 12 C gas breathing valve, in 12 C-filled liquid collection tank and 12 C reheating device is provided with 12 C-vaporizing pressure unit, 12 A reheating device is installed between the gas cylinder and the C-type reheating device. 12 C-gas filling mass flow controller.

7. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 3. 13 C 12 The device of C is characterized by: The high-purity CO2 filling system consists of a high-purity CO2 liquid collection tank and a high-purity CO2 gas reconstituted flexible coil. The high-purity CO2 liquid collection tank is equipped with a high-purity CO2 gas inlet pipe and a heated nitrogen inlet pipe. The pipes are respectively equipped with a high-purity CO2 liquid shut-off valve and a high-purity CO2 heated nitrogen shut-off valve. A nitrogen venting channel is provided below the high-purity CO2 liquid collection tank, and a high-purity CO2 gas breather valve is provided above it. The high-purity CO2 gas reconstituted flexible coil is connected to a gas cylinder at the rear.

8. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 3. 13 C 12 The device of C, characterized in that The vacuum system consists of a rotary vane vacuum pump and a silencer. The vacuum pump is connected to the entire system via a pipeline. A vacuum diaphragm valve and a vacuum resistance gauge are installed on the pipeline, and a one-way valve is installed behind the silencer.

9. A high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2, 13 C 12 The method for producing the device of C is characterized by, The method includes the following steps: 1) System preprocessing: This includes checking the system piping, visual inspection, and checking for errors during startup; if no problems are found, proceed to the next step; if problems are found, issue an alarm for further inspection. 2) Vacuuming: Nitrogen purging is used for 5-8 hours. 3) When the nitrogen in the system reaches the set value, industrial CO2 is introduced and purified to remove impurities, generating high-purity CO2 raw material gas; 4) It enters the low-temperature purification distillation column, where high-purity CO2 feed gas is generated at the top of the distillation column; 5) High-purity CO2 feed gas enters 13 The reaction is carried out in a C-type negative pressure low-temperature distillation column to produce high-purity CO2. 13 C 12 C; 6) Separately, high-purity CO2, 13 C 12 C is filled using its own filling system.

10. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 9. 13 C 12 The method for producing device C is characterized by: The specific method for purification and impurity removal in step 3) is as follows: 1) Industrial CO2 gas high-boiling-point impurities removal cold well removes high-boiling-point impurities from industrial CO2, mainly including water, carbon dioxide and hydrogen sulfide, reducing their content to below 500 ppm. 2) CO2 gas: The CO2 low-temperature adsorption membrane mainly removes low-boiling-point impurities from CO2, and the overall content of CO2 gas impurities is reduced to less than 6 ppm through the CO2 low-temperature adsorption membrane. 3) The high-purity CO2 feed gas mass flow controller is mainly used to count the amount of CO2 feed gas used, in order to further improve... 13 C extraction rate is used as a reference.

11. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 9. 13 C 12 The method for producing device C is characterized by: The specific method in the low-temperature purification distillation column in step 4) is as follows: First, the sample enters the purification distillation column for purification. Then, this invention employs a cascade arrangement of high-efficiency structured packed columns and random Heli-pak packed columns connected in series, with a total of m stages of structured packed columns and n stages of random Heli-pak packed columns. The first-stage distillation column uses a conventional purification distillation column, while the second-stage distillation process uses a structured packed column. The structured distillation column can provide a basis for subsequent enrichment. 13 C provides a large quantity of semi-finished products. Random packing has a smaller feed gas handling capacity compared to structured packing, but the equivalent theoretical plate number of random packing is much higher than that of structured packing. 13 The latter half of the cascaded C enrichment system is designed with n+1 stages of random Heli-pak packed towers, while the m-stage structured packed towers are mainly used for large-scale separation. 12 C gas, thus obtaining crude 13 C is the feed gas; the latter half, n+1 stages of the random-packed Heli-pak tower, utilizes the ultra-high separation efficiency of random-packed materials to rapidly enrich the gas in the top phase. 13 C gas.

12. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 10. 13 C 12 The method for producing device C is characterized by: The 13 Gas C is obtained at the bottom of the final stage of the scattered Heli-pak packed tower, and this gas enters... 13 Product C accumulates in the liquefaction collector, and is then vaporized and pressurized by the bottom electric heater. 13 Product C gas passes through 13 Product C gas is reheated to room temperature via flexible winding in a tube. 13 Product C's filling quality flow controller controls the filling flow rate, and finally... 13 The C-grade electronic balance accurately measures the filling amount of the steel cylinder using milligram-level precision.

13. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 10. 13 C 12 The method for producing device C is characterized by: The 12 C gas is collected at the top of the final stage random-pile Heli-pak packed tower. 12 Product C is first stored in 12 C. Liquid collection tank, when it needs to be filled, 12 Nitrogen gas at room temperature is introduced into liquid collection tank C as a... 12 C vaporization pressurization heat source, through 12 Product C gas recovery flexible winding tube 12 C. Reheat to room temperature. 12 The C product filling quality flow controller is used to control... 12 C. Gas filling speed, cylinder filling mass is determined by 12 Product C is filled using a gram-level electronic balance.

14. The high-efficiency negative pressure low-temperature distillation method for producing high-purity CO2 according to claim 10. 13 C 12 The method for producing device C is characterized by: The 13 The exhaust gas from the C-type negative pressure low-temperature distillation system is high-purity CO2 gas. It can be collected periodically into a high-purity CO2 liquid collection tank. When vaporization and filling are required, room temperature nitrogen can be used for vaporization and pressurization. Then, high-purity CO2 gas is used for warming and reheating in a flexible winding tube to room temperature. Finally, the cylinder is filled directly using the partial pressure method.

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